Hypothetical Engine Upgrade

waynerp

waynerp

Dedicated Member
British Zeds
Joined
Jun 8, 2015
Points
44
Location
Kent
Model of Z
2.8
Hi All.

Lets say I wanted to 'upgrade' the engine in my 2.8 Z3.
This definitely isn't about speed but more about power and noise.
As much as I love my Z, having had V8's for nearly a decade as our main family car, and recently downgrading to a 2.0l diesel, the rumble of the X5 V8 is no more.
So I have been wandering, if I was to look a bit further into putting say a 4.4 or 4.8 BMW in to the Z, and remembering that I am a 'newbie' DIY mechanic, who would like to attempt at doing this myself, what is the realistic consequences of putting such an engine in the Z3. Would it be too much power and handle terribly? i'm just thinking of the 80's and merchant bankers wrapping their 911's round lamp posts!

I have looked at a few X5 and some older 7 series engines on ebay. I assume that i would require all the electrical / wiring to make it work. Does this mean i would also need the ECU and ignition from the donor car?
Would I also need the brake system from the donor car? What other parts would be required?

I'm just toying with this idea and dont want to sound reckless, I just like the thought of having something different with a bit more grunt and rumble, but still having a BMW heart under the bonnet.
Just want some advice / recommendations before this goes any further
 
waynerp said:
Hi All.

Lets say I wanted to 'upgrade' the engine in my 2.8 Z3.
This definitely isn't about speed but more about power and noise.
As much as I love my Z, having had V8's for nearly a decade as our main family car, and recently downgrading to a 2.0l diesel, the rumble of the X5 V8 is no more.
So I have been wandering, if I was to look a bit further into putting say a 4.4 or 4.8 BMW in to the Z, and remembering that I am a 'newbie' DIY mechanic, who would like to attempt at doing this myself, what is the realistic consequences of putting such an engine in the Z3. Would it be too much power and handle terribly? i'm just thinking of the 80's and merchant bankers wrapping their 911's round lamp posts!

I have looked at a few X5 and some older 7 series engines on ebay. I assume that i would require all the electrical / wiring to make it work. Does this mean i would also need the ECU and ignition from the donor car?
Would I also need the brake system from the donor car? What other parts would be required?

I'm just toying with this idea and dont want to sound reckless, I just like the thought of having something different with a bit more grunt and rumble, but still having a BMW heart under the bonnet.
Just want some advice / recommendations before this goes any further
Click to expand...
My advice unless you are a serious mechanic ,engineer and can do without your car for 18 months ,get a hammer and a nail knock a few holes in the exhaust ...instant power gain,well no power gain but it sounds like it lol
 
Anything possible, your only limited by time and money :) I have seen a z3 with the V8 so its possible easiest way would be fit the engine and use a aftermarket ecu :) there are plenty of brake upgrades though you will need harder springs on the front because of the extra weight i'd imagine.
 
Dickymint said:
Anything possible, your only limited by time and money :) I have seen a z3 with the V8 so its possible easiest way would be fit the engine and use a aftermarket ecu :) there are plenty of brake upgrades though you will need harder springs on the front because of the extra weight i'd imagine.
Click to expand...
Aftermarket ECU?
do you know where i can look at these?
thanks
 
Look like any newbie could do the conversion - with 30 years of mechanical and engineering experience behind them, plus at least GBP10k !:whistle:
 
MegaSquirt is the one that I would use, plenty of info on the net and its quite easy to use but there is others :) with a after market ecu you can use it to control fuel and spark and most rolling road tuners can set them up for you but its easy to install and set up using a laptop and its easier than you think as they pretty much take care of themselves, as for fitting the lump that's also easier than you think as in the past I have fitted all types of engines to my cars, I remember walking around a scrapyard once with a tape measure to find the biggest engine that would fit my Cortina ;)
Pity you didn't live nearer i'd love a project like that :p
 
To do a conversion takes a lot of serious planning, Mark aka Deano took a lot if time, money and skill to convert his car, it is not for the faint hearted. You need to be prepared for the unexpected and when a problem does rear it's head be prepared to tackle it head on. This sometimes involves serious cash.

I sincerely do not wish to patronise you or make assumptions about your skill set but if you are a beginner or novice mechanic, pay someone else to do the conversion for you, if you strike up a good relationship with the builder perhaps you can labour for him/her to gain hands on experience.

Just my 2p worth, hope I did not offend.
 
Now another option for about 2.5K is to fit a supercharger, this is a relatively easy option and can be bought in kit form from the states and take a weekend to fit, This will give you both power and noise. :)

edit: link added

http://vf-engineering.com/z3-1997-02/
 
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Deano doesn't live far from me and believe me it is one very professional installation with far more gone into it than meets the eye as he has done all the work himself down to the last nut and bolt and if I said he had spent £20k it would probably be conservative. He is an engineer by trade and knows his stuff and has reinforced the rear subframe area himself by calculating stress loads etc. so knows what he is doing. He used a Chevy LS2 engine which are ideal as they are a pretty shallow unit and can be purchased in a crate with all the ancillary gear to compliment them for such conversions. I am not saying it can't be done but the BMW V8 units tend to be quite tall so are a harder proposition to fit in the engine bay with different obstacles to overcome however I do understand people's desire to keep it OEM as possible.
 
Brian H said:
To do a conversion takes a lot of serious planning, Mark aka Deano took a lot if time, money and skill to convert his car, it is not for the faint hearted. You need to be prepared for the unexpected and when a problem does rear it's head be prepared to tackle it head on. This sometimes involves serious cash.

I sincerely do not wish to patronise you or make assumptions about your skill set but if you are a beginner or novice mechanic, pay someone else to do the conversion for you, if you strike up a good relationship with the builder perhaps you can labour for him/her to gain hands on experience.

Just my 2p worth, hope I did not offend.
Click to expand...



Hi Brian, of course you didnt offend, I am honest in my abilities ( or lack of, in the mechanical sense ) which is why i asked here. I was hoping someone would say yep just pull out the old and slap in a new engine and away you go. looking at the thread with the chevy engine its clear that it is way way above my skill set.
Maybe i will look down the supercharging route, but i really love that V8 rumble, not sure if a supercharger could replicate that
 
Anything is possible, Just been reading the straight 6 magazine and there is a bit of a write of somebody who had a V10 from the E60 M5 fitted into a 1M. was about £25 k to do it.
 
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